I hope you will enjoy some of the games as much as i do.
Here is the top 15 strategy games for linux.

1. Battle For Wesnoth

The Battle for Wesnoth, or simply Wesnoth, is a free turn based strategy game designed in June 2003 by David White.

David White based Wesnoth on the Sega Genesis games Master of Monsters and Warsong (also known as Langrisser). He wanted to create a freely-available, open source strategy game that had very simple rules, but had a strong artificial intelligence, and was challenging and fun.

2. Warzone 2100

Warzone 2100 is a real-time strategy and real-time tactics hybrid computer game, developed by Pumpkin Studios and published by Eidos Interactive. Outside of the story, Warzone 2100 only has a single faction, limiting some of the variety that can be expected from such games of its kind, although the faction is very complex. Essentially, Warzone 2100 plays much like Earth 2150 with 3D units and terrain, customizable vehicles, a lack of traditional standing infantry, use of “research” to acquire new technologies, and perceptible differentiation of vehicles types.

3. Spring

The game is mainly focused around multiplayer games over the Internet or a LAN connection. There are currently a few single player missions, built on the basic support for this through Lua scripting. There are also many skirmish AIs under development, allowing for offline play or extra players in an online game. Two skirmish AIs ship in the game package, as well as three maps and the XTA mod.

4. Battle Tanks

“Battle Tanks” is a funny battle on your desk, where you can choose one of three vehicles and eliminate your enemy using the whole arsenal of weapons. It has original cartoon-like graphics and cool music, it’s fun and dynamic, it has several network modes for deathmatch and cooperative — what else is needed to have fun with your friends? And all is packed and ready for you in “Battle Tanks”.

5. Bos Wars

Bos Wars is a futuristic real time strategy game (RTS). In a RTS game, the player has to combat his enemies while developing his war economy. Everything runs in real-time, as opposed to turn-based games where the player always has to wait for his turn. The trick is to balance the effort put into building his economy and building an army to defend and attack the enemies.

6. FreeCol

Is a turn-based strategy game based on the old game Colonization, and similar to Civilization. The objective of the game is to create an independent nation.

You start with only a few colonists defying the stormy seas in their search for new land. Will you guide them on the Colonization of a New World?

7. Freeciv

Is a Free and Open Source empire-building strategy game inspired by the history of human civilization. The game commences in prehistory and your mission is to lead your tribe from the stone age to the space age…

8. Glest

The core game allows the player to take control of two completely different factions: Tech, which is mainly composed of warriors and mechanical devices, and Magic, that prefers mages and summoned creatures in the battlefield.

9. Widelands

If you knew Settlers I & II™ (© Bluebyte), then you already have a rough idea what Widelands is all about. Yes, it is where the inspiration for Widelands came from.

In Widelands, you are the regent of a small tribe. You start out with nothing but your headquarters, a kind of castle in which all your resources are stored. In the course of the game, you will build an ever growing settlement. Every member of your tribe will do his or her part to produce more resources – wood, food, iron, gold and more – to further this growth. But you are not alone in the world, and you will meet other tribes sooner or later. Some of them may be friendly and trade with you. However, if you want to rule the world, you will have to train soldiers and fight.

10. FreeRA

FreeRA is an open source implementation of the famous game “Command and Conquer – Red Alert”.

11. Jagged Alliance 2 – Stracciatella

Jagged Alliance 2 is a tactical role-playing game for Linux and MAC.

Didn’t manage to the top
These games didn’t manage to be in top 10 list, but still worth to check them out and maybe try them.

12. FreeOrion

FreeOrion is a multiplayer, turn-based strategy computer game, inspired by the Master of Orion series.

13. Snowballz

Take command of your army of penguins as you blaze your path to victory!

14. UFO: Alien Invasion

It is the year 2084. You control a secret organisation charged with defending Earth from a brutal alien enemy. Build up your bases, prepare your team, and dive head-first into the fast and flowing turn-based combat.

15. Crimson Fields

The outcome of the war lies in your hands. You decide which units are sent to the front lines, and when to unleash the reserves.